Prevalence of diabetes in Asian Indians based on glycated hemoglobin and fasting and 2-H post-load (75-g) plasma glucose (CURES-120).

OBJECTIVE With the introduction of glycated hemoglobin (A1c) as a method of screening for diabetes, it is essential to study how use of A1c would affect the prevalence of diabetes in different ethnic groups. We compared the prevalence of diabetes by fasting (FPG) and 2-h post-load (75-g) plasma glucose (2-h PG) and A1c criteria in an Asian Indian population. RESEARCH DESIGN AND METHODS Subjects (n=2,188) without known diabetes were drawn from the Chennai Urban Rural Epidemiological Study, a population-based study in Chennai, South India. FPG, 2-h PG, and A1c estimations were carried out. Prevalence rates of diabetes were compared using as cut points FPG ≥7 mmol/L (126 mg/dL), 2-hr PG ≥11.1 mmol/L (200 mg/dL), or A1c ≥6.5% criteria. RESULTS Prevalence of diabetes was 6.1% (n=134) using the FPG criterion, 10.1% (n=221) by the 2-h PG criterion, and 12.8% (n=281) by the A1c criterion. Thus the prevalence of diabetes by the A1c criterion was 110% and 27% higher than the FPG and 2-hr PG criteria, respectively. Only 121 of these subjects were identified by all three criteria. Subjects diagnosed by the A1c criteria had the lowest FPG, 2-h PG, A1c, and serum triglyceride levels. CONCLUSIONS In Asian Indians, use of A1c criteria would result in markedly higher prevalence rates of diabetes. It also identifies a different set of individuals with milder glucose intolerance and lower serum triglyceride levels.